Depending on how resilient your body is (how well it can take punishment, aches and pains), the right shoes may or may not be all that big of a factor. Personally, I need good running shoes because I have gone through plentiful injuries in the past, which have severely weakened certain parts of my body, especially my knees, tendons and back. So, for me, shoes are very important.
Basically, you want to get a shoe that offers you good stability. You want a shoe that's going to offer support to your foot and your ankle, which can greatly reduce stress on the joints and tendons in your legs, even up to your back. Your shoes should be tight, but not too tight. You don't want loose fitting shoes, as they won't offer any support (and they'll actually do more damage than anything), but you don't want shoes that are extremely tight either, as they will cut of circulation and decrease bloodflow, which can also be harmful to your body.
The shoes that I wear are . I bought them a couple of years ago when I still lived in Chicago. At the time, they ran about $140, but they were well worth the cost.
These shoes work for me because they offer excellent stability and cushion my heel very well. They also keep my foot aligned properly, which drastically decreases the amount of pain that I go through when I run. I partially tore my achilles tendon when I was younger and I have suffered through plenty of back injuries, as well as the routine punishment of my knees (I played catcher in baseball), so shoes are very important to my body when I run. I'm not saying that the exact shoe that I wear will benefit you - because our bodies are all different - I'm just offering you some advice and telling you what works for me.