I have a 458 Lott on order but I am having a problem finding load data. I have several boxes of Hornady bullets (softs and solids) in 500 grains. Does anybody have a source of loading data or some suggested losds to start from?

Youl'll find many loads if you do a search useing the "Find" button just above.H4895 is a very good powder.

I use in my 458 Lott IMR4320. I got some of my loads from STEVES LOADS on the web. My solids go
over 2300 FPS my soft nose gr 2280.

Try this

http://www.accuratereloading.com/458lott.html

Use the 3031 loads as starting loads for Varget and IMR 4064 and 4320.

And as Shootaway has indicated a search on this forum will turn up heaps of stuff.

Have a look at what you turn up and then post questions about some of the data you found which you like etc.