Craig.
Deeply saddened that this should have happened. Is there any further news on the situation? Lots of good advice on here already to check local bins, skips, alleys and gardens etc. If this proves negative, the thief is more likely to be a vinyl fiend than a town-chancer. Post the details on flyers at local events to keep the records' details in peoples' minds. The genuine soul community will be watching auctions and sales lists and will let you know if anything turns up.
Does anyone out there photograph their records? I have got an invisible ink pen that shows up under UV light but have not got round to using this yet - any thoughts out there? Finally, I keep a list of records and their distinguishing marks which gives a little peace of mind should some go AWOL.