Getting a larger table right now has been near impossible. For most groups you will want to split into smaller groups 3/3/4, 5/5, etc. That said Disney systems seems to choke on odd numbers so might look for two tables of 6 or three tables of 4, and try to get the times as close as possible. You can try to book online, but you might also try calling 407-WDW-DINE to book too. It used to be for larger groups like 10 you pretty much needed to call. Online booking opens at 6AM EST and Phones open up at 7AM EST.