Press kits are generally used for two purposes:

* To solicite work from promotors, club-owners, etc.

* To be used by the media for print.

For print, a glossy photo is needed, and the image also needs to be available electronically. Photos of one or two people need to be in a vertical format and should be slightly "right reading" (image, when printed on the left side of the sheet, should be oriented to lead the viewer to the right) or straight on. Worst case use, the image will be in one column (about 22 picas),
so background should be fairly stark.
It's probably good to spend the money to have images professionally shot. If done on the job, avoid using on camera strobes.

Copy should be written in a "T" form. That's because editors are often under tight deadlines and will choose the releases easiest to edit. The first paragraph should stand on it's own as a cutline for the photograph. Naturally, the copy should be available electronically as a text file.
For glossies, check out the back of Shutterbug magazine for houses that specialize in headshots and promo photos. They're really inexpensive.

For solicitation of work, it is appropriate to use images that have been offset printed.
Modern Postcard does a great job of reproducing photography on a normal size postcard stock for $125.00 for 500. You wouldn't want to try to reproduce a postcard image in a newspaper or magazine because it's laready been screened, and a dot patten would appear if it is rescreened.

The most impressive packages I have seen lately utilize either a two pocket folder (9"x12") with a die cut for a business card
or a custom printed 9"x12" envelope with a "teaser" in the lower left hand corner.

With the two pocket folder, you can put a personalized introductory letter in the left pocket and back-up materials on the right side. For mass solicitations, a postcard with contact info on the back is often sufficient.

Appropriate use of press releases sent to arts/entertainment editors of local newspapers and magazines is effective if the news is right for the publication.

The final product needs to be as professional as you are. In many cases, this is the one chance to make an impression.

Good Luck!

Russ