If you are in Vegas for more than a couple of days and wanting to eat authentic Asian foods at reasonable prices (not the type at Food Courts...), try the Vietnamese cafe 'Pho" at Treasure Island, they serve authentic Vietnamese noodles that even Asians from Asia enjoy!
For more choice, venture off 5 minutes from the Strip, at the intersection between Spring Mountain Road and Valley View Road, you will find Chinatown and all kinds of authentic Asian food from Korean to Thai.
Recommendations for Authentic Asia food in Vegas.
Todai is an upscale buffet restaurant featuring sushi, sashimi and other Asian dishes. It is very popular and offers quite a substantial selection. The quality is very good and priced between $20-30 depending on lunch or dinner. It is located in the Miracle Mile Shops at the Planet Hollywood hotel & casino on the South side.
Noodles is a small restaurant inside the Bellagio offering a good selection of noodle dishes, soups, appetizers, etc. at a reasonable price by Strip standards. The Pad Thai is very good. The restaurant is not really geared to parties of more than 6 but does offer the solitary diner or couples many seating options.