Unfortunately, 2011 was the first year Lego gave away a minifig as part of the May the 4th SW promo. In 2010 it was a SW minifig sticker sheet and 2009 it was a SW minifig poster with around 150+ figs limited to 15000 copies. I don't believe there were any May the 4th promos prior to 2009. I'm pretty sure 2009 kicked it off because it was the 10th anniversary of Lego SW.
As far as promotional SW minifigs, here are some of the ways Lego has done special figs besides the ARF trooper & the upcoming TC-14:
*Gold C-3PO (2007) & chrome Vader (2009): randomly inserted into sets from their respective years
*Chrome Stormtrooper(2010): TRU promo in the US
*White Boba Fett (2010) & shirtless Darth Maul (2012): given out at Legoland parks
*ANH Medal Ceremony Luke (2009) & Han (2011): Lego SW Visual Dictionary & Character Encyclopedia, respectively
*Young Han Solo (2011): Padawan Menace DVD
Hope this helps, I wasn't sure if you were interested in just the May the 4th promos or other special minifigs so I included both.