i would agree with the Fender Reverb advice. start off with a good amp. i have a Pro Reverb, but the Deluxe is more desirable. the only bad thing with an old tube amp is, you guessed it, old tubes. i need to overhall this thing which will cost me some $$. the electronics need work too, the thing pops and clicks and the fuse is temperamental.
after that, you can upgrade your guitar. a fender strat is definitely gunna give you a "strat" sound (eric clapton) and a les paul is gunna give you a "gibson" sound (slash from Guns and Roses). j’s sound isn’t really either, cuz his guitars are pretty customized. telecasters are great, but they give you a pretty distinct sound that you may not want. i guess you should decide if you want new or used equipment. and if you want used, do you want vintage? if you can find a good deal on a nice vintage guitar, i would get it regardless of the type. as far as new guitars, shop around for the best deal and what you like the most. a new Fender Jazzmaster reissue is not going to sound much like J mascis until you change the pickups and run it through a bunch of effects with a marshall stack. but at least you have a sound you are looking for.
ps i’ve got a gibson 335 that doesn’t sound too great distorted since its a hollowbody, so stay away from hollowbodies!! (i was into playing jazz, which is where i made that mistake!!)