Hi,
Take a look at the Vonage USA website. They offer a USA phone number which you keep/send out to contacts in the USA. When they call the number, it'll be forwarded to you here in the UK. I don't know if it's free or what the charges are etc though. Check their personal section and the small business section of the site and compare. I think this is a similar setup to what sugarplumgirl mentions with Skype as well, so between these two and any other similar service I think would be your best bet.
The next stage to think about is call quality. With bigger and faster broadband capacity and connections, quality should be good. However, as you mention business use, then you might be away from your home or office here in the UK and that might mean you relying on the domestic cellular carriers for a good data signal. The now 'old' 3G network should be good enough in most areas of the UK, it does drop out in more rural areas etc though with blackspots in more densely populated areas. 4G is the current provision that has greater capacity or bandwidth. However coverage isn't as good as 3G and you need a 4G capable phone and plan to access it. That all said, pretty much most of the time you should get decent signal and data coverage.
In addition to these above, a quick google search found me this
https://www.globalcallforwarding.com/info/international-call-forwarding.aspIt's a complete service and will do and provide exactly what you are looking for. However, do check their rates etc.
Lastly, I don't know if it would help you but I'll suggest anyway. For perhaps the last 5 years or so, I've always had a DUAL SIM mobile phone. Initially, they were entry level to mid range smartphone levels, but in the last couple years, all the top end flagship mobile phones have a Dual SIM variant as well - except Apple, they probably wont offer one until its time for the iphone 17!. What this means is whenever I'm in the USA, I don't have to carry two handsets, it's just the one. I pop in a local USA SIM card and all good. You can't buy these phones in the UK high street, you need to purchase from specialist mobile phone suppliers and there's a big choice nowadays.
I haven't purchased from here yet, but my next handset will be from them;
http://www.mobicity.co.uk/They have the best range of Dual SIM handsets I find and they are very well priced too.
Another is;
http://www.expansys.com/ My last handset - Microsoft 535 Dual SIM was £94 delivered from them and I've been really happy with this handset over the last 6 months. I'm going to change it soon only for a larger screen.
Another is;
http://www.handtec.co.uk/ Last time I purchased from these guys was back in 2007'ish. They have a decent selection as well.
Hopefully, out of all the above, you'll find a combination of services that will suit you great!
Cheers, DtM! West London & Slough UK!
PS - I'm selling the Microsoft 535 and a past HTC Desire V - both Dual SIM. If you'd like one to try then I'd sell for £55 and £40 (respectively) delivered to you in the UK. Drop me a PM if that might interest you.
