First off, there are lots of fits that work for stealth bombers, but everything on your ship should serve a purpose, and everyone has their own tactics for what they think is best.
Secondly without perfect fitting skills you'll have to make some compromises, it's up to you what you want to compromise but remember everything on your ship should serve a purpose.
Here is my null sec fitting on my Nemesis.
- Prototype 'Arbalest' Torpedo Launcher - X3
- Cover Ops Cloaking Device II (duh)
- Bomb Launcher I
- Phased Weapon Navigation Array Generation Extron (aka Target Painter) - X2
- Medium Shield Extender II
- Small Shield Extender II
- Micro Auxiliary Power Core I
- Nanofiber Internal Structure II
- Small Hydraulic Bay Thrusters I
- Small Warhead Calefaction Catalyst I
I'm still not fully committed to the dual target painters, but it works for now. Due to the powergrid of the Nemesis I've almost always been forced to put the Micro Auxilary Power Core on to fit the ship how I want.
Ok, now on to tactics. The Stealth Bomber is NOT a dogfighter in the sense that you can just uncloak next to a ship and hope that your torpedoes are going to be sufficient to kill them before they kill you. To be honest I hardly use my torpedoes unless I'm following up a bomb with one volley before I warp away. Patience and proper planning will be your biggest ally.
If you know what system you will most likely be bombing in you need to do some preplanning before you ever head out to engage your future victim. Gates are a great place to bomb victims and so are stations. Each gate or station should have a minimal of 4 OP (observation points) preset before you set out. One above, below, right, and left of the most likely place you'll be launching your bomb. Lets pretend we're going to bomb a gate. I personally like to set my OP's 300km in each direction around my target. I cloak up and warp to my OP, then click on the gate and select "warp to within 50km" and you'll fly directly at the gate and now be 50km away from your destination. Turn on your tactical overview, and zoom out so that you can see the full grid in space. Hover your mouse over the bomb icon and you'll see a bubble appear showing you if you launched your bomb right now, the area of effect the bomb will be effective in. Bombs do not have any targeting and will only launch in the direction your ship in facing.
Set your bomb area to the area you intend to bomb, do this by clicking "align to" whatever you intend to bomb (the gate in our example). Stop your ship about 30km from your target and then sit and wait.....and wait....and wait. Patience is the virtue of a successful bomber. When the time is right and you are ready to bomb, click "align to" your target to get your velocity up, uncloak, launch bomb, and immediately warp to your OP that is opposite of the OP you warped to initially. For example if you set yourself 300km to the right of the gate, you'll want to warp the 300km LEFT of the gate. You'll already be all full speed, and pointed in the direction you want to warp so you will quickly warp away before anyone can hurt you. You should also click your cloak again once you are in flight to recloak up again.
If you think your target is slow, or if they are a bigger target and you know they'll have a few extra seconds to have to target you, you can turn on your target painters, launch a volley of torpedoes, and then warp away and cloak. Typically if you stick around for a dogfight you'll likely be killed. Stealth bombers can't take much damage.
The above tactics work just fine for solo bombing. One point I'd like to add though if you are going to be doing fleet bombing tactics is that you all need to be using the same type of bomb. Each type of stealth bomber gets bonuses to a different type of bomb damage. If you are in a fleet of 3 Nemesis, 1 Manticore, and a Hound, then you all need to be using Thermal Bombs. If there are more Hounds than any other type of bomber, then you all need to be using explosive bombs. The reason is, each bomb type has a 99.95% resistance to it's own type of damage. If 4 bombers are all using different types of bombs and all trying to bomb the same target, then whoever's bomb goes off first will destroy the other 3 bombs before they do damage.
Trying to be a stealth bomber pilot in high sec or low sec CAN be done, but you'll be playing by an entirely different set of rules. There are no bombs allowed in High sec or Low Sec, so all you will have to use is your torpedoes. Torpedoes can hit pretty hard, and the bigger the target the harder they hit, but also the more hitpoints the ship your attacking will have. Going toe to toe with a frigate or destroyer will be guaranteed you'll lose your bomber. A cruiser with most likely kill you with little problems. You can take on a battlecruiser or battleship if you can stay ahead of their guns, keep them warp scrammed, webbed, and target painted. A flight of drones flying at you is almost certain death so choose your target wisely.
The enemy signature radius, your torpedo explosion velocity, and of course your skill level are all key factors into how much damage you'll do. Three stealth bombers, one with a TP, one with a webber, one with a scrammer, can easily take on a battleship as long as they can speed tank the guns being shot at them. You can do this solo too, but friends are always welcome :)
If you are truly interested in doing some fleet bombing, but you don't know how to get started to meet new bombing friends check out a channel in eve called "Bombers Bar". It's a public channel where bombing fleets are organized daily. You don't have to leave your corporation to join up in one of their fleets, and most of the gents I've met are fairly nice and willing to help you out a bit. Don't be stupid though, always warp cloaked, bring the same bombs as everyone else, and NPSI (not purple shoot it).
I hope this helps any of you thinking about sitting in a stealth bomber, although I'm sure plenty of people will disagree with my advice, because there is always someone out there that needs to point out they know more than you, etc. Just a reminder for those people, I've been playing eve for 3 1/2 months and these are my newbie reflections.