When I first bought Logbook Pro I had somewhere around 9000 hours. What I did was enter the data flight-by-flight through my first part 135 job where my flying became very consistant (i.e. same airplane type day after day). That didn't take too long (first ~1450 hours, i think) and was a good way to learn how to use the program.

Next I created a new "Aircraft" type called "Transfer" for each category/class/type. I then made one entry with the totals from each page. i.e. "Transfer DC9", "Transfer BAe-3201", etc. With this I was able to get through the entire logbook in a reasonable amount of time and I still had the breakdowns by type, engine, class, category, etc. This is key for using the powerful search and totaling features for filling out applications.

I'm now going back through and replace each "Transfer" page one at a time with the individual entries. The overall totals and search results don't change for filling out applications but I'm making progress toward eventually having everything entered in full detail.

Of course I've kept it current with new flying since the time I started using it.