iPhoto is an OSX only program. It's not available for the iPad.
In iTunes, with your iPad connected, select it from the Devices list. Go to the Photos page at the top. You can turn on Sync Photos from iPhoto, and either sync everything or selected albums. Photos will be optimized and added to the Photo app on the iPad. You can not edit or delete photos that are synced by this method on the iPad. They must be changed in iPhotos and re-synced.
You can also turn on PhotoStreaming if you have iOS 5, the latest OS X Lion update, and the latest iPhotos version, and iCloud. This will automatically share your last 1000 or last 30 days of photos between your iPad and iPhotos. You might want to turn of automatic uploading and importing in iPhotos preferences to prevent massive photo copying when you don't want it.
This is about all you can do with iPhotos directly on the iPad.
There are a multitude of other photo organizing and editing apps available for the iPad. If this is not enough there is bound to be one (or a combination) that will meet your needs.
