Just had a butchers around the internet and found that the show dates are 12th - 15th of May, and entry is roughly 45 Euros per car + driver, and 10 Euros per extra person.
Been looking at hotels, and it really depends what we're willing to pay, as to where we go.
For me and 2 mates for 3 nights, I've found a hotel just off a motorway service area, for £298 all in. (£100 each)
Or a hotel next to the lake on the south shore, with all mod cons, for £736 all in. (£245 each)
There are other hotels further down the page that are a few miles from the lake