I've been using Greased Lightning for years--great stuff! I buy it at Walmart in the section where they stock other household cleaners such as Fantastic, Simple Green etc. I've also seen it in my grocery store and I would think Target may carry it too. To help you spot it, it comes in a bright yellow 32 oz. spray bottle with a yellow, white and black label. If you can't find it at your Walmart, it is a HomeCare Labs product (P.O. Box 491150, Lawrenceville, GA 30049) and most likely they can tell you which retailers in your area carry it.
Regarding sugar soap--I'm not familiar with that, unless you mean sugar body scrub?
Lowe's carries it.
Sugar soap in North America is Trisodium Phosphate, also known as "TSP". You can find it at any hardware or home improvement store. I think even Walmart carries it in the paint department.