How many versions is there for the T Mobile Sidekick?

[mßåßësm]

1) How many versions is there for the Sidekick? (Can you tell me the names of each version please & tell me the year they were released!)
#2) Also I have a Sidekick LX (brown) is there other versions for the LX with updates or something or is there just one LX?

I know a little bit about the Sidekick & certain versions but I would like more info =)

Thanks =)