Rigale is a gameplay modification to Warband. It adds many new features, like guilds, exploration system, quests, quite extensive crafting, epidemics, village specialties, many new skills (scouting, camping, shamanism, bard, mining, ambushing...), gathering system, shamanism, exhaustion system, and many other things
Overall, towns and villages sell very very few stuff; You might want to check for fairs, that will give the merchants much more goods and money for trade