looking at my options

I bought a 95 Nissan Altima about 6 years ago for $5,100 and it had 75k miles on it. Now it has 130k and it still runs fine but there are a couple problems that have me thinking. Today I had to get the intermediate pipe replaced and the O2 censor tacked back in. That was $230, and since the engine light is on it would need another $400 in repairs to get the engine light off and pass inspection in August 2007. The car may be in overall decent condition but due to its age and the need for rather expensive repairs, I was thinking about getting a new(used) car by August 2007 so I can donate this car.

I know you really didnt need to know about all that stuff but I figured I'd let you in on my situation.

So I have 2 questions for you guys. First, based on what I listed here, what is your guys' opinion of a good car for me?

- smaller car (corrolla or similar sized)
- $10k-$15k range
- nothing fancy like leather seats or GPS or whatever
- decent performance but isnt that critical

Also, what is a good age and mileage for a car that is still in very good condition but has a significant price drop?