Hello, neighbors!

I thought I would tap into the Hive Mind to see if anyone has information regarding home energy audits.  Recommendations or bad experiences with specific companies, in particular.  I'd also like to know if you thought it was worth it, or any other commentary you might have.... since the going rate seems to be in the $300-$1000 range.  Did you recoup your costs in energy savings? Tips, tricks, stuff you wish you'd known or asked?

Or, did you also have freezing cold walls and somehow solved it yourself? :)

Thanks so much for any help!