About typing /tpa requests, you can type in the first three or four letters of the player's name and most of the time, the /tpa command accepts it. Such as /tpa san for San57x100 or /tpa droc for DrOctagonapus48. But sometimes it's not that accurate, because if both RedFocus and myself are on, I usually get the /tpa red requests for some reason.
So take it one step further and hit the tab key after typing the first few letters. The chat will automatically type the player's whole name. Like if I type /tpa cool and hit tab, it will become /tpa coolquote, if he's on.