In the US, you generally expect bicycles to get cheaper towards October/November, rather than May/June/July.
Everyone wants to buy a bicycle when Spring gets nice and Summer. Then, they'll ride a few days in the fall and put the bike away in winter. So, sales tend to decline in the Fall/Winter (and the deals come out), so looking in Fall is probably the best.
As for tricks to get bicycles at cheaper prices, you could look at shops in different areas which may have different costs (locally, some bikes here are more expensive than going to one of the cities a few hours away; however, some manufacturers may have price control) or look used (but it seems like you're looking at relatively high end bikes in this case, so you may not have as much luck with it). You may also get a good deal on accessories with a bicycle (a certain amount of free kit in some places), so you could hawk those on eBay or something to recover some money.