'.net' is the one to go for.
The "Big Three" are '.com', followed by '.net' and '.org'.
'.info' has a bad reputation. It is generally associated with cheap, spammy sites, and conventional wisdom maintains that it is harder to rank (although some disagree with this idea).
'.us' is generally considered better than '.info', but it would depend upon where you are geographically, and where your customers are. (If you're in the USA and your products/services are designed to appeal to US based customers only, then it makes sense. However, if you or your potential clients are in Europe or the UK, or in Asia, then it would probably be less practical. I would avoid it personally, and would certainly prefer ".net" if it's still available.