<<...but how did this happen and is it worth downloading some retrieval software or going into town 30 miles to visit local tech?>>
Anything manmade...can malperform...at anytime. Something could operate as a trigger for nonperformance...it may just happen that a critical element suddenly becomes missing or unable to perform.
Only you can determine the value which should be placed on the files you currently cannot access.
I will say this: I have a program which has enabled me to retrievd data from troublesome/failing hard drives...and each file I have has nothing but a personal value to me. I have the software because I see no sense in not having it...if the possibility exists that I may need it someday. I don't expect my hard drives to last forever or to always behave appropriately. I have backups...but if it can be retrieved (at a neglible cost), I will retrieve the data.
My software cost me less than $100 and has proven useful on two occasions....it's part of what I consider the cost of playing with computers every day
Not all recovery software costs...I just find that I feel more confident in the software after I've tried it and it's done the job. I don't mind then paying for it, just as I pay in excess of $100 per month for Internet access, cable TV, and digital phone.
I don't have to buy the software monthly