I've slowly been collecting the Charley's War reprints that Titan have been producing for a number of years now. I've filled a few gaps via the Forbidden Plant shop on Shaftesbury Avenue (in central London) where the books are often in the remaindered section priced at £4.99 each.
I've just noticed that all 10 volumes, plus the omnibus volume, are available on their website at £4.99 each. If you buy 1-2 volumes the postage the P&P is only £2, which is pretty darn reasonable.
Link is here so what are you waiting for?