Not bought any vinyl in a while and when I do, am now limited to a dodgy old belt drive turntable on a cheap old stack hifi that spends most of its time in a box in the storage room. Whether you should get involved with vinyl really depends how serious you are though mehro as it won't be a cheap or easy undertaking these days.
In terms of a deck they've got better over the years but can be a bugger to find as only specialist stores stock them (as well as accessories like cartridges) while some of the high end ones are bloody expensive. You can pick up reasonably good mid priced direct drive decks from the likes of Stanton or Technics which would serve you pretty well though while you'll also need a decent amp if your current system doesn't have a separate one.
Finding vinyl will be your next problem and will depend greatly on where you are based and what you listen to. Much of the new stuff (other than dance music) is is either not released on vinyl or gets a very limited release which unless you are in a large city or are up on your mail order music will be nigh on impossible to find, even the older stuff is seldom found outside of a few specialised shops and the second hand shops where you may find some old gems and bargains but may also pay through the nose for the "collectors" status of vinyl and may suffer from seriously variable quality replete with cracks, pops, hisses and jumps. I find it hard to listen to Primal Scream's "Higher Than The Sun" without the deep resonant pop that my double vinyl of Screamadelica gained when a blim jumped off my spliff while I was leaning over the decks at a party in France but that's part of my memory, I wouldn't fancy paying collectors prices for a lump of plastic with somebody elses carelessness etched into the sound.
If you get past the equipment and vinyl sourcing issues there's also the slight issue of portability to contend with, particularly if you're going for the John Cusack type collection. I've got over 3,000 LPs and 12"s and 500 or so 7"s and they are a bitch to move around, I only shipped 400 or so of the more essential stuff when I moved to Asia so I'm paying for storage on the rest (along with a few other bits we didn't need) but if you're planning on moving home or particularly country often then the weight and transport cost issue is worth considering.
Even storing vinyl can be a pain, too hot they can warp, too damp and the sleeves go mouldy and musty, I even suffered some flood damage to one box that was stored in the Unis basement nightclub where I DJed. Your shelving for a major collection will also need to be industrial strength, none of your PVC, plywood or formica CD racks from IKEA, you'll need 2" timber framed shelving either well braced or preferably bracketed into the walls for a major collection (factor this into the moving issue as well).
Don't get me wrong, I wouldn't sell my vinyl for the world and still prefer the warmth of the analogue sound. If I ever get to retirment then the house will have a proper music room with deck setup and racking for my vinyl but at the moment all of that is a pipe dream leaving me with my mp3 player on the move and the steady slog of converting my vinyl to mp3 format when I get any free time at the weekends and fancy facing the wrath of a wife who believes sitting in the spare room cueing tracks individually is antisocial.
