I found it was bearable as long as I ate plain stuff little and often - it seemed to get massively worse when I hadn't eaten for a bit, and anything really sweet like a bar of chocolate, or artificially sweetened like Options hot chocolate drink, was deadly. Avoiding anything which I had even the slightest aversion to also helped - tea and coffee went pretty quickly, as did meat and chicken, bananas, salad veg and cake-y type stuff, plus diet coke as it just tasted of sweeteners to me.
For lunch at work I'd take in the same kinds of things as I'd have done before, but in such a way that I could eat a tiny bit at a time if I was at my desk (sandwich cut into six squares, grapes rather than an apple, ryvita for nibbling at, tiny bits of cheese scone, those Heinz soup pouch in a cup things rather than a jacket spud from the canteen, etc.). Porridge for breakfast always helped too, as long as I could go straight downstairs and make it quickly as eating early helped lots.
For dinner, in each pregnancy I went at least two straight weeks eating only pasta, cheese and tinned tomatoes.
I tried ginger beer this time, and it worked quite well as long as I also had Gaviscon in my handbag.... Also drank a ridiculous amount of soda water and diet indian tonic water, both of which made me feel a bit better.
Finally - toothpaste was the enemy. For the first trimester I ended up using an electric toothbrush with a tiny round head and the merest suggestion of toothpaste, with my mouth wide open to try not to trigger the whole gagging thing. Once I got past about 12 weeks I found that if I could avoid being sick when I brushed my teeth the day would be generally OK, but if I gagged while brushing I'd had it.
Finally lifted at 22 weeks.... Thank god this will be my last pregnancy!