DallasBill is right DSLReports is the best site ever for DSL questions.

I wanted to add though, that if Covad is available in your area now, you might want to check out SpeakEasy. They are a Covad reseller but most of the time (magically) they are cheaper than Covad. Anyhow, I've never had any problem w/ their customer support or service and they have a prequal tool on their site.

http://www.speakeasy.net/

Take care,

-SF