Hey LanthyPhair, I went to CU-Boulder as an undergrad and have stayed working at the university as a prof. research assistant while taking time off before going to grad school. I lived off of Table Mesa & Broadway in Boulder and really liked it. It's a few miles south of the university, but there are multiple bus routes (the Skip, Dash, 204, for example) that are around the area. There are quite a lot of complexes in the area as well. I lived in a townhome in Tantra Lake Apartments (they have both townhomes and apartments) but there are lots of complexes around the area (e.g., Coronado Springs, Stanford Apts) and it is far enough from the noisiness of the undergrads, but still close. (And there is a grocery store right on the corner of Table Mesa/Broadway). Boulder is certainly pricey for one bedroom apartments unfortunately. After I graduated I moved a little outside of Boulder to Superior/Louisville (down the highway about 10 minutes) and moved even further this past year (still only 20 minutes away).
For some of the previous posts that are saying you need a car, that's absolutely incorrect. There is fantastic public transportation in Denver/Boulder and the metro area. (They actually received an award for the fastest growing or something along those lines). The only reason I'm willing to live as far away as I do is because I just ride the bus in and out everyday. It's nice to just sit back and relax and read or something.
Good luck in your search and feel free to message me if you have more specific questions! Boulder is beautiful, and I'm sure you'll love it. Just take advantage of the gorgeous weather, pleasant scenery, and multitude of activities!