The first time I ever won a giveaway was about 2 days ago for 10M. It was a huge one, I got 2nd place.
As for the drop parties...usually there's a best spammer award of 100K-1M. I almost ALWAYS win them (I don't know how to autotype though).
Then say the person drops an item...wait 45 seconds, then at the last 15 seconds spam click like hell and you'll get it. I got a Zamorak Platebody from that (one of the best items at one of the drop parties).
Here's my daily log of all I've made following these two methods up there ^. And those were only F2P drop parties...