Be warned: if you're sending a DVD, make sure it's the best possible quality. Professional quality. Not a clip from a camcorder, locked off in the corner of a pub. It will say "amateur band" faster than you can get to the chorus of the first song on it!
For a pub band, keep it simple. I send:
1. Demo CD - good quality and well mixed with contact details on. Best song first. 3 or 4 track tops. Print the label if you can using your computer (you can buy sticky CD labels from Smiths)
2. Letter saying hello - again with contact details on
3. Setlist
4. Business card (again you can buy template card from Smiths and get great results with a home printer)
If you've got a band logo - print that on everything. Looks good.
I'm going to start including a flyer with our upcoming gigs on (makes you look busy and in demand) and a photo.
Bottom line, you're better off leaving stuff out of the envelope unless it looks slick.