Complex sentence: HP was the second largest seller of tablets in the US (after Apple) and the HP TouchPad was the second most desired tablet for the period from January to October 2011, selling 204,000 units in total.
Split into simpler sentences: HP was the 2nd largest seller of tablets in the US (after Apple). HP's TouchPad was the 2nd most desired tablet for the period from January to October 2011, selling 204,000 units in total.