Suggest that you look way back in the Basics and you will find some info on starting into this game. Many guys agree that the best entry-level rig is based on the .308 Win. cartridge - the idea being that they are cheapest to shoot and to get confidence you have to shoot a lot. All of the drops and wind info are available - there ain't no secrets with that cartridge and it is a nasty killer out to 600 yards or so.
The whole secret is to shoot a lot - more than most guys could ever think of. How much is a lot - varies with the shooter but one of my .308 rifles has 4970 rounds thu it in two summers.
You might consider a Win. M-70 Stealth, Rem. M-700 VS or various Savage heavy barrels (new one have an acceptable trigger apparently).
If you buy one of these and a good scope you should shoot it till you start to understand wind doping and serious marksmanship requirements. I practice from 700 to 1000 so that I can hunt with confidence at 500-650, some guys shoot a lot longer, some not quite as far..
You should understand that to get into long range shooting you should learn to start keeping notes on your drops, wind settings, temps, bar. pressure, loads etc. There are way too many numbers involved in this game not to keep a record book.
Rule of thumb from some guys here who really know their stuff - plan on spending the same $ on your scope and mounts as you did on the rifle. That just plain works. Good luck and don't be shy about asking for assistance - this is the right place, there's a lot of knowledge and experience here.
Repeat after me - .308 Winchester! .308 Winchester! .308 Winchester!