GAIN AMPS

I would recomend saving up a little more. it will really be better in the long run trust me.
 
Your options are

a) Get a shitty stack new. Behringer, Crate, Marshall, Line 6, and Randall all have an offering in the price range. None of them are very good or really worth the money you'll drop into them.

b) Get a mediocre stack used. Maybe a used Mesa/Marshall/Avatar 4x12 cab and a crappy head?

c) Save up. $800 will get you a new Avatar 4x12 cabinet with $300 left. save up another $3-500 and you can get a Peavey 5150, Line 6 HD147, Mesa Single Rectifier, Laney GH100Ti, etc.. there are a lot of good tube amps that go used for under $1000.

Try hard to get a good cabinet. Avatar makes great cabs for very good prices ( avatarspeakers.com ). $500 for a 4x12 loaded with your choice of speakers shipped. A good cabinet willl be something you can keep as a part of your rig for practically forever, but heads can come and go fairly easily.

If you buy a shitty Crate, Marshall, Behringer, etc. stack new, remember you just threw away however much money on stuff you're going to want to replace with new stuff anyway.
 
I just bought a 6505+ last week as well. It's fucking MEEEAAAAANNNN!!!!

Don't let ANYONE tell you that it doesn't have any balls compared to the 6505 regular. Maybe the 6505 has a little more gain, but gain doesn't necessarily mean good tone...and how much gain do you really need? Get a used Marshall 1960 cab, preferably one with vintage 30s, such as the 1960AV...you can get a brand new one for about 600 or used for about 350-400. Save some money and get the 6505+...its only about 50-100 bucks more and it has a clean channel that's twice as good as the regular 6505.

By the way, if you're going to be playing live, a slant cab isn't the way to go. You lose a lot of sound buying slant cabs. Get a straight cab, trust me.
 
ebay is the best place, but you can also try musiciansfriend.com or music123.com.

They sell their stuff wholesale and it's brand new. You can get some good stuff really cheap.