Actually, most of the bigger bulb growers offer scant advice on fertilizing lilies other than to say that the bulbs don't really require any fertilizing - they should get what they need from any kind of decent soil. I've grown lilies all my life and have never fertilized them other than mulching the beds with compost every year (as I do with my entire garden).

If you feel you need to fertilize, any rose or tomato/vegetable fertilizer will work well - something like a 5-10-10. Apply when the shoots first emerge and again just as the buds are swelling before flowering. Or a single early application of a controlled release fertilizer for flowering plants (first number lower) will work equally well.