Just in time for Father’s Day and the warm summer weather, Vistaprint is offering customized t-shirts for $5.99! Even sweeter, new customers can also get free shipping on these t-shirts, making them just $5.99 shipped right to your door. These t-shirts usually run for $10, so make sure you take advantage of this limited time offer. If you’re looking for a fun and unique Father’s Day present, check out the Father’s Day themed designs in Vistaprint’s gallery. Make your Father’s Day gift personal with shirts that say “Super Dad” with the ability to customize with photos, “World’s Greatest Dad” with the option to turn your family members into caricatures, designs…