Incorporating in CT
First of all reserving the name in Connecticut is actually not required, you can simply file the Articles of Incorporation with the chosen name, provided its available and does not include restricted words.
In addition to filing Articles of Incorporation with the state you would need to obtain an EIN and file for S-Corporation Election with the IRS. As far as sales tax ID goes, typically service providers are not required collecting sales tax, however in order to provide you with a definite answer I would need to know exactly what your business would do and sell. You might need to obtain specific licensing or file for tax ID number anyway if you plan to hire W2 employees, etc.
You are welcome to visit our Connecticut Corporation page to learn more about forming how to form one.