None of the hotels in Lopburi - all typical Thai/Chinese style -- are particularly good. Unfortunately there are no guesthouses, though we think there's definitely scope for a monkey-themed one.
If for some bizarre reason the Nett Hotel is full, Lopburi Asia is your next best choice. The rooms are well-sized and clean, plus it's within spitting distance of the ruins, though morning traffic is a bit noisy. They have western breakfasts available in the small downstairs... Read our full review of Lopburi Asia Hotel.
The Nett Hotel certainly has the prettiest mural in town and for the money the rooms are pretty good too. The location is central and it's close to market food and Lopburi's small selection of restaurants. Traffic noise isn't too bad either thanks to its location on a small soi. English is... Read our full review of Nett Hotel.
The Lopburi City is reasonably close to the train station and the Kala Shrine. It's not popular with travellers, however - the staff were bemused we were even thinking of staying there. The rooms are a bit grotty side and light sleepers would be annoyed by the train noise. No English... Read our full review of The Lopburi City Hotel.