I had Ghostery before, but you have to realize that those ad blockers also have tracking lists you can subscribe to.
The web bug issue has been around ages now since the early 00's . There is a tool called Ad Muncher that I used before for ads and web bugs etc. MVPS Hosts can block web bugs etc, combined with the regular ad blocking is all you really need IMHO ! Also running too many extensions can have adverse effects, so having one take care of everything for privacy, ads etc is ideal. Also you can be tracked by your ip even using a proxy, but a lot of people don;t seem to understand that. The only way to not be tracked online is to stop using the internet !