Google Scholar allows you to track who is citing your publications. On the main page begin by selecting "My Citations"
For all citations:
On the right hand side you will see a breakdown of your citation indices:
The h-index indicates the largest number h such that h publications have at least h citations. In the example above, 2 publications have at least 2 citations. One of those publications may have 500 citations; however, the other may only have 2 citations. This is a balanced indicator of influence. The i10-index is simply the number of publications that have at least 10 citations
Selecting "Citation Indices" brings a full screen chart of citations over time.
For specific citations:
You can also see who is citing your article and in what paper the article is being cited. On the "My Citations" page select the number under "cited by" for the article of interest
You will then be directed to a screen of all the articles that have cited that paper. You can also select the name of the article where you will see a screen similar to this one below. Here you can get a breakdown of citations over time.
How do I get notified when a particular paper is cited?
Search for the title of your paper, e.g., "Anti de Sitter space and holography"; click on the "Cited by" link at the bottom of the search result; and then click on the envelope icon in the left sidebar of the search results page (Create Alert)