I\'m not sure if it was asked, but I couldn\'t find anything like this.
My program uses a simple .txt file for log purposes, It just creates/opens a file and appends
First, check you're only logging things that are useful.
If it's all useful, make sure it is easily parsable by tools such as grep, that way you can find the info you want. Make sure you have the type of log entry, the date/time all conforming to a layout.
Build yourself a few scripts to extract the information for you. Alternatively, use separate log files for different types of entries.