the main singing section of Home Park is the Devonport End so if your willing to make alot of noise and sing with the green army head to that stand and the first Brighton shirt i see i will by a pint
You can't buy online but there is expected to be about 11,000 spare tickets as there usual gate is around 6,000. You can book one from their fans fest but the ticket will be in the main stand not the Davenport end. So long as you get there early I'm told you'll be fine.