First I went to the county website and was able to run a plat search and found my lot which contains all of the measurements (and easements). Not sure if you're county has a website that you can do that but either way, go to the county to get the plat. I decided that instead of a possible argument with my neightbors I hired a surveryor for $300 who staked out my lot line. Sometimes you can find the markers that are buried (see the plat it has the location of the markers) but I couldn't find any of them and neither could the surveryor (he used GPS). Also, my city had an ordinance related to fences (i.e. set back rules) so you'll want to check that out too.
