As has already been said, it's best to discuss contraception options with your doctor. There are a lot of options out there (more than most people realise!), so there will be something suitable for you.
Personally, I take Yasmin and my weight didn't go up or down when I started taking it.
There are some pills that are considered better for skin, like Diane-35 and Brenda... Yasmin is one of the few that is not associated with weight gain as a side effect. Although, the weight gain experienced on other pills is usually minimal and temporary, and according to most of my friends, in the breast area...
IUDs can be useful, implanon works great for some people and not other, the depo injections also work really well for some people. Just need to make an appointment to discuss all of these with your doctor.
There's some great information at the FPWA (family planning WA) website at http://www.fpwa.org.au
Oh, and remember - if you are NOT in a completely trustworthy monogamous relationship, or you DEFINITELY DEFINITELY can't have children right now, always combine your contraceptive pill with condoms... the pill doesn't prevent STDs!