Welcome to the forum Ajay and there may be larger IT companies here that sponsor overseas people but I'm not too familiar with that field myself.
Mike our administrator who posts often enough may be able to suggest some companies but another way of doing it would be for your husband to have a look at online employment sites like SEEK - Australia's no. 1 jobs, employment, career and recruitment site
or careerone.com.au and look for vacancies in his career area.
He may recognise some global companies and could get in touch with them or with any companies for that matter though the situation is probably a bit varied right now as it has been all around the globe.
As to visas, be it an employer sponsored visa or an independent skilled visa, for a family you will have a primary applicant and the partner and children become secondary applicants attached to the prinary applicants application.
The sponsored and independent routes do have their different approval systems and if you start by having a look at Workers - Visas & Immigration
you can see what each way entails, there also being advantages with either, main ones in my opinion being:
An employer sponsorship could be quicker and no points testing involved but the visa is dependent on remaining employed with that visa - there being at FAQ - Subclass 457 Visa Holders Affected by the Economic Downturn
some examples and applicable irrespective of what the reasons.
A 457 can lead to a PR
visa and independence from employer/employment situation but it is a lengthy duration approach.
On the other hand, applying for a PR
visa outright, a 175/176 or a provisional visa like a 475 you need to have qualifications assessed as a first step and at a click on to Skilled and other Professionals from the first link above and then on form1121i in top para. you'll have the listing of occupations and a reference to assessing organisations, generally ACS for computing professionals, their web sites/contact details at end of listings.
A positive assessment attained, a visa application is generally straightforward enough though what category your husbands assessment places him will determine how quick an application will be processed, ie. if his occupation is on the Critical Skills List, it should be processed within about 12 months and if he sought a state nomination [a 176 visa] it would be quicker.
Have a read of information in sticky thread #4 re current processing priorities.
If you click on Visa options at Professionals and other Skilled Migrants - Workers - Visas & Immigration
[and by now you'll appreciate it is a simple menu driven system] you can choose 'outside Australia' and you'll have 175/176, 476 and 475 and by selecting whichever visa you'll get headings along a top bar that include the main ones of 'eligibility' and 'applying for this visa' , the former having a self assessment table and the latter also a checklist that should be referred to and a visa costs link.
I'd suggest you and/or your husband treat the exercise as a project much as he would with programming as there's a lot of relevant links to be read but all info you really need is on the site.
My own personal approach if doing an application would be to print off an application form along with the checklist [both to become your own copies] and go through doing a fill in and making up a To do List.
When I had the Checklist and Application form both fully ticked off point by point, I'd consider I was ready to make an application.
It is important to be thorough for an immi report a year or so back quoted that on average over the four years to 2006 something like 160,000 applications per year were not being accepted and that's about $2500 in application fee kissed goodbye.
[Wasn't showing as answered, so see if an edit does the trick]