Outdoor lighting

My partner and I recently purchased a mhp and will need lots of help. Thank goodness for sites like this. We need to replace the outdoor lights that illuminate the streets. What type are the most efficient (i.e. most cost effective)? Where can they be purchased for a reasonable price?

ebay is where i have had the best luck. i love this site too, you can learn a lot through this forum.

I give the credit to the handsome moderators, of course.