$300 is dirt cheap. Heck, at most weddings I've done film and processing come to more than $300.
Out here in the midwest U.S. I'd say the average price for wedding photography (5 or 6 hours or so) is around $1200, and there are plenty of photographers charging two or three times that much.
If the bride is trying to get wedding photography done for less than $300 she either hasn't priced wedding photography, or she really doesn't care much about capturing the memories of "her most special day".
Good call, Voodoo. It's hard work, and unless she's a really good friend or family member, there is no reason for you to get less than $300. Heck, I thought you were'nt charging enough. I've shot a few friends' weddings, and I considered it quite a discounted rate to charge around $500 for a full wedding and reception (they thought it was a great deal too). Keep putting out the ads, lot's of folks would jump on a $300 wedding photog.