Questions...

I have a Ravin exhuast (Z55 series)(1 muffler splits into dual exhuast) setup in my 98 Trans Am, and my first question is...If i got SLP long tube headers would i need anything else for them to hook up and work with the exhuast...such as a Y pipe? would a Y pipe work with the single muffler?

Secondly, SLP has a Head and Cam package. What else would i need for that to hook up and would i need a new transmission? i have stock automatic in my TA would it be able to handle that power or would i need to switch to manual?

Not immediately, but some where down the line you'd need a new rear end, especially if you already have other mods on the car, and will be putting out some serious numbers. The factory ten bolts are weak. Your automatic should be fine for now. If you're looking for lots of hp down the road, you'll need things like a tranny cooler, torque converter, etc. for the transmission.

As for going with the SLP LT's, I'll be doing that in the future, and you'll need a new y-pipe for sure. If you have to have cats on your exhaust, I'd get some hi-flow cats at the same time, and have them put on when you switch the headers as well. I don't need cats here, so I won't keep them when I do the header swap. I'll just put some straight pipes in there when I do mine. SLP offers a y-pipe that's meant to go with their LT headers, since the headers relocate the cats (which is illegal in some states). Look for this as well.

any idea if the SLP induction ram air kit is worth it or not? they say adds 22 horse over stock ram air i really dont believe that

What SLP ram air kit is that? Are you referring to the Cold Air Induction, like what's in my sig, part #21033? Looks like this...

http://www.stealthperf.com/store/images/items/21033.jpg

If so, I doubt you'll see that much gain unless you were running a built setup under optimal conditions. But, the more mods you have, the more collective gains you'll see, that's true for any car...