Where do I find the manufacturing date of my phil&teds evolution or cocoon genius?

The date stamp is located on the seat shell on the lower back section/lumbar area, under the fabrics. There are two ways of conveying the date ('clock' and 'table') of which depending on the seat date either could be used. How you read these dates is listed below:

manufacture clock
Manufacture clock shown on infant capsule. Clearly shows year (07) and month (April). Therefore this car seat was made in April 2007.
J F M A M J J A S O N D
07 o o o o o o o o o
08 o o o o o o o o o o
09 o o o o o o o o o
10 o o
11
European date stamp found on some UK ECE 44.03 car seats.
Not all squares may contain a dot
Top row - month
Column - year (11 = 2011)
Dot on last square shows manufacture date, this one about shows F/10 which means it was made in February of 2010.
It is important to note that the dots are always raised and should not be indented, an indented dot may have been added by someone who is not authorised to do so.