I can't say much about the food but for props, I'm not sure where you live but some great props to use on the buffet or around the house can be found at places like the discovery store sometimes if you have an Egyptian Coptic or Eastern Orthodox church in your city, they will have fundraisers and sell various Egyptian things. Pyramid's and papyrus could be great decorations. You might try ebay to see if they have anything.

Methinks your theme idea is great. As for guests being asked to gear their costumes towards the theme? Yes and no. Why not send out a 'Save the Date' postcard earlier in late Aug or early Sept..informing them of your new theme party for Halloween and list 2 or 3 BIG prizes for the "Best Egyptian Costume"? The prizes may be their incentive to get going on their costume creation!
Maybe google 'theater rentals'-if one is near where you live? You might be able to get ideas how to make things or rent them, if affordable.
I was thinking..(OH NO!)..if you could rent a female manniquin (sp?) & dress her as Cleopatra, then using 2 long pieces of PVC pipe painted gold-you could staple an Egyptian throw rug or fabric around the poles to make a seat & place Cleo in a sitting postion on the thing. You could then put 4 'S' hooks in the ceiling and by using some chain painted gold-suspend the display in an unused corner of the party room.
Another thought-get sheer fabric in Egyptian colors & drape from the center of the ceiling & extend to the 4 corners of the room-adding cobwebs hanging in front of it.
Maybe you could use a role of white paper tablecovering & paint a mural to place on 1 wall or behind your food table-with the Nile River in the foreground and desert in the middleground and a pyramid in the background.

Oooo...another Halloween party enthusiest! Enough to make me come out of lurkdom for awhile...

Great theme! We have a themed Halloween party every year, themed costumes are required (I think it actually makes it easier for people, because they have an idea to start with). And no, our guests don't seem to have a problem with it, we just give helpful hints in our invitations, and we normally have next year's theme picked out ahead of time. This year we're doing a pirate theme...all of our guests were informed of that at last year's "Hollywood Academy of the Undead Awards" party. Our 2009 them is going to be a medieval theme - we get a little ahead of ourselves sometimes. ;-)

Some great suggestions so far, and don't forget to start saving cardboard boxes to make pyramids with (a large one out on the lawn that you have to walk through to get to the front door would be very striking and mood-setting)! I guess it depends on what you prefer...my hubby likes "scary" better, so our decorations normally have some sort of gore factor to them. If you lean towards that, you need some clear jars for "canopic" (spelling?) jars...to hold the organs of the dead (in the pyramids). Otherwise opague jars labeled will work just as well. Heiroglyphs on the walls would be a nice touch, along with eyes watching from behind things (think glow in the dark paint).

As for your costume, how about you going as a mummy! Tear up some old sheets, stain them with tea (and a little fake blood, if you like), and have your hubby wrap you up. Or "wrap" some old clothes to make them a "mummy suit", then just make yourself a head piece and booties to match.

You could be one of Egypt's animal gods too...a bird, or a cat, something they worshipped. But don't let your size stop you from finding a great Isis costume or something - those flowing dresses make anyone look good, really. Sandals, a head piece and some jewelrey would finish it off.

Food...I'd probably go with some organ molds & jello and/or cakes, but like I said, we do "gross". Our normal halloween fare is a "serve your own" chili bar, with all the fixings, lots of desserts (witches fingers, chocolate eyeball truffles, etc), and a full bar with a "signature" drink. Last year's was the martini (since we were all supposed to be TV or Movie stars or characters), this year we'll pick something to fit with our pirate theme (a rum-based drink). I normally have punch with dry ice in it to fog it up too.

I'd do a search for "Egyptian Halloween" and see what pops up. Go through web sites and see what everyone has to offer for egyptian theme parties, and you'll be surprised at how many ideas you'll end up with (too many to pull off, no doubt). If you have a basement, perhaps you'd want to decorate that as if you were descending into a pyramid, with treasures and a large sarcophogus down there? We used fake torches to light our basement stairs for our goth party one year, so it was like descending into a vampire's lair...

Just a few ideas - can't wait to see what you come up with! Fun theme! :-)