I installed bootcamp and then windows xp on the 30gb space of drive I left. Now everytime when I start my mac it boots to windows! how can I boot to mac osx

Go into the Control Panel on Windows (Did you install the BootCamp drivers?) and navigate to the "Startup Disk" icon. Double click it and tell it to boot to OS X.

Alternatively, when you restart your machine, hold down 'Alt' and then you can choose which OS to boot to (that time only)

If you want to default it to Mac OSX, you can set that in the Mac side, under System Preferences, Startup Disk.

If you don't know how to get back to MAC OS X from Windows XP, this is how. Look down in the right hand corner where the clock is, you see all the icons beside the clock? Look for a grey diamond, it should tell you it is BootCamp when you put the mouse cursor over it. Click on that and it will give you the option to restart in MAC OS X. From there do what k3v said above me. Now, I just thought of something else. Did you install BootCamp in Windows XP? If you didn't, you need to put OS X Install Disk 1 DVD/CD in and install it, otherwise there are other things that won't work correctly (Apple drivers neded by windows to use your Apple hardware correctly). If you have already done that just do what I said above and you will be good.

Hope that helps