The first project sounds like all you want to do is eliminate aftershocks so your program does not use them as input. Eliminating quakes by longitude I don't think is the best approach for eliminating aftershocks.

The second program sounds like it could be easily done on a spreadsheet. No programmings required. The NEIC list can be output in comma delimited format which a spreadsheet can import automatically.

A free spreadsheet program can be had with Open Office. I've used it. It's not bad.

Brian