Head for The Hills, everyone -- Heidi Montag and Spencer Pratt are engaged! Spencer got on bended knee and propose to his GF of eight months at a resort in Santa Barbara on Tuesday, an insider tell Us Weekly, adding that Heidi's "over the moon!"

Maybe it's because she got her perfect engagement ring -- a diamond-encrusted platinum band with a pink stone that Spencer bought the day before (and Heidi hand-selected). "They looked really happy," a spy at the jewelry store says.

We think it's safe to say that Lauren Conrad won't be the maid of honor.