As a method to get a working version of a resource booking system up and running asap, i used a custom list type made by James Finn -
http://www.codeproject.com/KB/sharepoint/SharepointReservation.aspxIt seems very good, especially when compared to the MS Template - everything seems to have been working well for about a month now. There are no overbookings, edit & delete work and you get proper messages if you try and overbook !
The one very minor issue is that for reoccurring bookings, they don't seem to work for bookings spanning multiple days, which isn't really an issue for all but one of our users (therefore it's not an issue at all).
Oh and it means a list for each of your resources, which is a bit different to the MS Template.
Pete
Nothing is as it seems, nor is it otherwise.