Hamburger

http://www.aquariumfertilizer.com/ If you don't mind buying a bunch of ferts, this place has some good prices. Shipping is a bit expensive but doesn't increase much with each additional bag. Most bags are one pound ...of a PURE compound. Mixes are available. I guess you are looking for more than one pound though...

They have some Parrot's feather at Aquagiant, that is a very nice stem plant. I have some milfoil of my own (not m. aquaticum though) and it is doing fine with no CO2. It has grown a good inch in the past 5 or so days and I only have 1.4 WPG. I'd take the L. sessiliflora off your hands if you are willing to ship it. By the way, tank looks nice. Hope your algae problems go away.