Hello there. My stepfather collected approx 30 Ion Idriess books and he has since died. Just wondering what to do with them. We would like them to go to a good home. List attached. Cheers in advance.Steven
Hi Steven, condolences on the loss of your stepfather.
Can I start by echoing what "siggins" says above. The monetary value in all of your books is probably equal to your copy of The Cattle King. If you are looking to get these to a good home then may I suggest listing them on eBay - there is still good interest from folks wanting to read Idriess' books and who don't really care if it is a 3rd or 30th edition of the book - they just want to read.
I'm sure there would be collectors who would like some if not most of these, but perhaps you should consider selling them, or some of them. This site (Idriess.info) has a Bibliography listing all Idriess' books and has a guide to what the books may sell for (this is a guide only - some sell for less, and some a lot more). As a general rule, first editions sell for more than later editions and earlier works of Idriess tend to be worth more than books published at a later date.
For example, you have listed a first edition of The Cattle King and this is probably the most valuable book in the collection (if it is a true first edition - there were something like 11 editions/reprints of this in 1936 alone!). So it is listed in this site as $100 - $200 (in very good condition, but no DJ) and $200 - $400 (in very good condition with good DJ). The Opium Smugglers is also valuable if in good condition and even more so with a DJ.
You can check out the other prices, but I note that Forty Fathoms Deep is NOT a 1st ed (1st ed was 1937, not 1943) and neither is Over The Range (again the 1st ed was 1937 and not 1941).
You may even be able to advertise them on this site. Perhaps Clive has some more ideas.