it'll depend really...
For me, information technology A-Level was literally a course on using business applications, it wasn't so much a gateway specifically into IT, but into any business that'd use standard applications. it covered simple programming, using applications and an introduction to the law regarding IT and information systems (such as Data Protection).
I imagine that a degree would be much more in depth.
the problem with generalised course titles are that there is no strict structre as to what the course will entail, you should find that if you pick a college/uni then they should have a summary of the course, course content and how the work will be marked (i.e theory tests vs practical work and coursework etc).
Also you really need to think about what field you'd like to go into and how well you fit within that field.
I mean there are lots of different regions of IT,
not least
windows
Linux / UNIX
MAC OS.
but also working with computers will cover things like
PC support - building new machines by physically putting bits in the box
building new machines meaning installing software
Desktop support, as a combination of the two above but also troule shooting applications and figuring out why things aren't workin and how to make them work.
Server support, like desktop support, but instead of just figuring out why outlook isn't working, you'll also have to figure out if it's a problem at the server level.
server application support - working with specific applcations suce as IIS or apache, or database servers.
DBA - Database administrator - working specifically with databases, installing, creating, maintaining, optimising etc. (and again this can be split down into the specific database, ege. MSSQL MYSQL Oracle Postgres etc.
then again you might want to specialise in networks.
not talking about setting up a home network but more setting up office networks and VPNs, learning how to work switches and routers firewalls etc.
A sysadmin might have responsibility for all of the above tasks within a very small company. -so there are lots of different things to keep you learning and interested.
you may wish to go into IT as an application developer, or software tester.
then again you could go with the security side of IT, ethical hacking, penetration testing etc,
if you have an idea of what area you'd like to go into it makes re-training better as you can work towards a goal.
Another thing you may wish to consider before paying out for a course is whether you need a course to start with, or whether some real world experiance would be better, -there is no replacement for a bit of paper that prooves you can do something, but also no replacement for a bit of experiance that prooves you can do something.
The way I got into IT was working for a small software house as their internal IT support, the only IT qualification I had was my A-Level in IT, I had that job for a lot of years, I was trained how to use a lot of things like Unix/Linux windows and Active Directory, how to setup and use firewalls and such, and how to be a DBA, I also learned a little of software and web development.
now it's fairly easy to get IT jobs because I have about 7 years experiance in IT working for various companies.
certainly comming from Sales you may do well to apply for a small company where they may take you on as a sales person and train you up in addition to the sales role that I assume you'd find it easy to fill. -many small companies may not have a dedicated sales person, you'd be an asset to them in that you have real sales knowledge and they could help you by taking you on as support person, slowly training you how their business works and how to find and fix problems etc.
from here you could get a taste of what bits of IT you like and choose a course that'd formalise your experiance with a bit of paper saying you can do it as well.