Hello,
You do not have to include a photo of yourself, I don't actually know anyone who does that.
A lot of people include a photo of the celebrity to sign however as some celebrities do not provide their own (in particular when sending via venue)
It is always best to include something towards the postage - You could try and purchase some stamps or IRC's on our sale/trade board here:
http://www.fanmail.biz/mboard/viewforum.php?f=127
A lot of members have their own little shops on here which are very helpful.
You could also send the celebrity a bit of money to cover the postage - It will show that you have tried your best to help them out. If there is no way of you doing any of this then simply add a few lines in your letter explaining this. But bare in mind that sending nothing to cover postage won't leave you with a very high chance of success.
Good luck with your requests {thumb2}