I recently got some tshirts printed for my DH's birthday from FotoFun or something like that at Deira City Centre. I got a photo put on my DD's tshirt with some writing. The only thing is that the tshirt must be white, they are not set up for colour tshirts. It was cheap too, around 50 dhs including the tshirt if I recall. You can also provide your own tshirt.
Next do t-shirts with ages on them but seen them in UK so not sure if stocked here. You could probably get one made at one of those tshirt stands in the malls