While certainly not an exhaustive list, these sites have lots of good information, links to other sites, and pictures.
Home page for the Battle of Bunker Hill Reenactment that occurred June 25th in Durham, NH. Has a fine list of links to other sites of interest.
Daughters of the American Revolution
A small but great web site. They have photos and descriptions of actual 18th century clothing.
The Continental Line
A page linking several reenactment organizations over the entire country. Lots of interesting links. You could probably find an event to attend somewhere every weekend in the summer!
A page listing schedules, events and requirements for Battle Road. Information for clothing, musket and instrument requirements.
18TH Century New England Life
A site for detailed clothing information of special interest to Battle Road participants.