Laptop and mobile internet

Need some advice. Hope you can help me out here.

My wife wants to purchase a laptop and be able to connect to the internet while not at a phone socket. So I need to know the best way to go about this. She needs the laptop for a stockbroking program, and needs to connect to the net to download updates from the market. Wants to be able to do it anywhere.

So what are my options? I guess a laptop with a modem, and a mobile phone with some kind of connection socket is the way to go. Any suggestions on what brand or model mobile would be good? Rmemeber I'm in Australia, too, so some carrier types may be out.

Any other options as well?

Thanks

[Xaotic]

Here you can almost do that with a pda, using wireless cellular internet. As for Australia, start with checking with cellular and internet companies and find out costs and areas of coverage. Depending on location, there also may be wireless LAN coverage in cities. Either way, the provider may have specific hardware that would be necessary, normally for a laptop it'll either be a PC card or adapter to be used with another device. As to that type of laptop, I'll leave that up to you, as I'm biased(probably in favor of my employer's products, but I'll never tell). It should have decent specs(not necessarily overwhelming), good battery life is preferable, and PC card slots, perferrably 2.