moonbug
Hi, I'm currently living in Suva and will be here until next July at least. I've met two other vegans in Suva and I hear there is another on on Tamavua.
In Suva you can get just about anything as long as you are willing to pay for it, though with imported mushrooms at $30/kg and on volunteer wages I've learnt to live without some things.
The Suva market is fantastic and is Monday-Saturday with Thurs-Sat being the biggest days (more range, fresher food). Lots of fresh fruit & veg at reasonable prices as well as indian spices, rice, dried beans and tofu. To give you some indication of cost you can get 3 pinapples for about $2, a drinking coconut for $1, a bag of bean sprouts for 50c and 5 small papaya for $2. Apples/pears are imported and therefore expensive too, so I tend to stick with the tropical stuff.
The range of products in the normal supermarkets varies depending on where you go but you can get soymilk, mock meat, tofu etc. There is also Cost-U-Less which imports alot of products and you can get vegan chocolate and a wider range of things like soymilk, cereal there. I've also found a great little chinese supermarket that sells rice noodles and soy sauce etc
Around 40% of Fiji's population are ethnically Indo-Fijian (the decendants of Indian indentured workers) and so there is lots of Indian places to eat and a number of vegetarian ones too. Most people understand what vegetarianism is and many Hindu's have at day or so a week when they keep vegetarian.
Eating out: I've found that not too many places used ghee in the cooking of curries (veg oil is cheaper), but they will have yogurts, ghee made sweets etc. There is also a Chinese community so you can get a tofu/veg dishes from lots of restaraunts. In terms of island food, I love cassava, but am not a fan of dalo (taro). The pineapples are the best I have ever eaten and mango season has just started. Make sure you try the vegetarian palasami, it's dalo leave cooked in coconut cream, really nice.
The local company Pure Fiji do awesome skin care/beauty products from local products and don't use animal ingredients/ don't test on animals.
If you have any more specific questions, let me know.