You can get these from most good boxscore sites (ESPN/CBS etc) with some simple code you are allowed to extract one personal copy of the data from these pages. Shouldn't take too long to knock that out.
Although I have to admit that most systems and thoughts that I have ever seen/tried involving errors and LOB have shown that there is very little real correlation between totals or wins and either of these two stats - meaning that you may be flogging not only a dead horse, but one that only had three legs in the first place - that doesn't mean you aren't allowed to look into it :) Just throwing out my experience to possibly help you out.
I have some info on the subject of errors per game from the last FoxSheets Baseball Systems release. In fact, the statistic errors per game was one of the lesser performance indicators if you were to play the team with less. Here are the numbers from last years' June, July, and August months, assuming you would play the team with the "better error defense":