I'm one of those people that are sick the whole 9 months. Here's a list of things to try starting with things that minorly help and working up to things that help more so if the previous one doesn't work move on to the next one:
1. eat all day long - carry something with you at all times
2. preggy succors, things with ginger, all the other food remedies people suggest
3. sea bands
4. change your prenatal vitamins to only be the bare minimum vitamins you need. sometimes the extra stuff like iron can upset your stomach.
5. (talk to your dr first) take vitamin B6 & 1/2 a Unisom. it may make you tired the first week but after that your body gets used to it. I got through pregnancy #1 using what I listed in 1-5.
6. Phenergan (this made me tired all the time but I only threw up a couple times with pregnancy #2 on this. The b6/Unisom combo wasn't strong enough for pregnancy #2)
7. Zofran (this was my saving grace with pregnancy #3 - I could actually function, wasn't tired all the time, never threw up.. but in order for it to work the best I had to take it at the same time every day regardless of whether I felt sick. It seemed to build up in my system and the moment I'd miss a dose, the next day I'd be unable to function.)