the night before the wedding

I am photographing my first paid couple. they have there wedding on saturday 27/10/2007 and they have a small party the night before the wedding (lelet el hena) on friday night, they are renting a small villa with a garden for the celebration.
the celebration will start at 9PM and i am paid to take pictures there too before the wedding, pictures of the to be bride and groom, friends and celebration.
i have with me the 350D body, EF-S 17-55/f3.5-5.6 lens, EF 50mm f/1.8II and the 580EX flash and my tripod.
my question is, should i go for indoor or outdoor pictures or both of them??
and if i am going outdoor, please tell me some flash technices to use so i won't get all these black backgrounds with extra exposed people and i also know that the bounced flash is the best, but i don't know how to use this way outdoor, specially that i don't have any refracting surface.

Read all of this:
http://planetneil.com …h-photography-techniques/

and this:
http://strobist.blogsp​ot.com …-balancing-flash-and.html

I think you should rent a backup first.

You need a complete set of backup equipment to shoot a wedding. Some better lenses would be advisable, too.

Backup equipment as stated before, another body and some faster lenses, especially since this is in low light. Id recommend the 17-55 2.8 IS, 24-70L f2.8... not cheap, but renting is a solution if your on a tight budget.

Geez, you meant 18-55 and I was racking my brain over a 3.5 17-55.

Yea, I agree... you need to rent/borrow a backup big time. It'd be worth biting the bullet and getting a second flash and faster glass as mentioned above too. My advice - rent another 350D, 17-55 2.8 and 580EX. I think the important thing here is that you've forgotten that you're being paid and a couple is holding you responsible to document this day for the rest of their life.

I don't know if you have rental shops in Egypt, but you need better gear, and you need 2x of everything. Beg, borrow or steal something anyway you can.