flag connectors and standard female spade connectors are actually the same, the only difference is how the metal on the wire receiving end is rolled.
Radioshack has the 90 degree flag connectors, but like all insulated terminals they are 10 times the price of the non insulated terminals, still if you need them asap get them from there and take a razor to the plastic insulation (so it fits).
If you have standard spade connectors and some patience you can convert them into flag connectors.
Take a set of thin needle nose pliers and hold the bottom of the wire receiving end. With a thin flat head screw driver open up the split. Once enough of the split is accessible for a thicker plier to grab it then grab it and bend it out. Don't worry about getting it flat just yet.
Once it's open enough you can use either a long needle nose plier or a vice to flatten it out completely.
Using some tin snips or a set of dykes (I am talking about wire cutters, not two lesbiens, although the latter might be more fun). Cut the outside edges off, about 2mm worth on each side.
Now for the hard part, you want to roll the metal upwards. You need a firm but thin round object, either a thick paperclip or maybe the base of a lollipop or a small drill bit.
clamp one of the above to the base of the terminal with a pair of locking plier and carefully wrap the terminal around it. Don't worry if it's not perfect, you'll be using a pair of crimpers to complete the job anyway.
Voila, you turned a regular spade connector into a flag connector. I've done it numerous times and never had an issue. But I order my connectors in 100 packs.