it depends on what your buying and who your buying it from.
say you order strings off of musicguymic on ebay. You will barely have to wait a couple days. Say you buy a uke off of him too. You will barely have to wait a week. Try out some strings. Its all just a matter of what you want to hear. If you want a mellow sound, try worths or D'addaros(i think i epic failed the spelling of this). If you want a brighter sound, try aquilas.
try some and let us know how you do.
also, you can generally use concert sized strings for a soprano ukulele. so if you want to buy from the store, here on UU, you can buy the concert sized strings and it should work out.
one more thing. if you have any further questions, try using the search forum towards the right of the toolbar on the screen. You will pretty much be able to find any questions and answers you are looking for, pertaining to ukulele,video games, KFC, and other food in general.
as always, keep strumming.