Recently active topics in Twitter tagged with list

All my friends' names don't show up in the drop-down list for direct messaging

Is it possible to combine two Twitter accounts into one?

i was following someone and now for some reason i'm not anymore, so when i try to follow them now it just gives the "oops an error occured. please try refreshing" message, but that wont work either. Anyway to just get them following me and vice versa working? or getting the follow button to work?

Some people disappear from my "followers" list when I block them, but others that have been blocked still show up. Probably 99% of my followers were spam accounts, so I started to block them... but there are about 20 out of the original 40 that won't disappear from the followers list, even if blocked. How can I get rid of them?

Is there a definitive list somewhere as to what constitutes SPAM on Twitter? I am confused how one could even receive SPAM since users choose whom to receive updates from on Twitter. For example, I subscribe to Woot, which sends me updates about its latest deep-discounted electronic products. This isn't SPAM, is it?