No problem. I tend try to read series like this in order myself, but since I get most of my books from charity shops it doesn't always work out quite right.
It's not essential to read the Reacher books in order, but there is a small amount of chronological background information that rusn through, so it helps.
You have a real treat in store!
I use a site called fantastic fiction.
key in the authors name, press search
and it will list that authors books along with
the date they were published.You can then
print this off for future reference.