Oh man, love this topic! One of my favorite hobbies. Personally I like the .270/30-06. They're 2 different calibers obviously, but damn near the same. IMO you can't go wrong with either on of them. They are both very accurate, flat shooting calibers.
I'd recommend a tried and true Remington 700 .270. That's what I use. No need for higher priced guns, as that gun will shoot better than you can operate it. It doesn't matter how well a gun will shoot, if you aren't good shooting it. Spend the bulk of your money on the optics. depending on what class of optics your looking at we can help you from there. IMO the 3 optic companies you should look at based on your price range will be:
1. Lower priced: For the lower end of the spectrum scopes, you can't beat Nikon IMO. They make a nice scope at great prices. Look at their Buckmaster line for your hunting needs. Run you around $300
2. Mid Range: A good middle of the road company is Leupold. Many, many hunters use their optics because they are good quality. If you want a nice scope but don't want to pay the prices of the high end companies, definitely take a good look at Leupold. I recommend their VX-3L line. Will run you around $900
3. High End: Here's the leap to truly exceptional optics. I recommend Swarovski Optik. Exceptional quality. You really can see a difference with these scopes. It's like watching everything in HD. I can't describe the clarity and brightness you get looking through their scopes. I recommend the Z6 line. Will run you approx. $2000
I've heard great things about Zeiss as well, however I have no personal experience.
Edit: sorry for the large images, I thought they'd auto-resize.