I was looking about 6 months ago. For a 4 bedroom house. We must have looked at about 20 or 30 places, and only two of those were arranged directly through the landlord. I was regularly scanning gumtree, loot, rightmove, findaproperty, local shop windows and all the other usual suspects.
Previous to that, I'd only looked for rooms in already occupied houseshares, in which case obviously you don't need to go through an agent.
What were your last two places? If they were one or two-bed flats maybe that's why your experience is different. There are zillions of 1 and 2 bed flats around so there will probably be more privately advertised ones out there. We were looking for a 4-bed house with fairly specific requirements so the choice was rather more limited.