I run into this problem all the time...and luckily there are loads of websites that can help you out. If you find yourself doing this multiple times per day...there are also plugins. After viewing the image, i would still suggest starting with the websites i list, and then post on the Typophile forum.
Feel free to add any websites you think have a higher success rate and i will modify my answer to include those i've used before or any site i find would be a more suitable alternative.
In the order i use them:
for PDF's, read this article from the community. You can use Adobe Reader plugins, OR the properties of the PDF will list what fonts have been embedded.
If you are still have problems finding a font, or similar font, Typophile is wonderful community to reach out to. Please note that forum #29 is not where you post these. The correct forum, at Typophile, for identifying fonts can be located at http://typophile.com/fontid