Pardon if someone has already mentioned it. No reason to be ashamed or to take any unreasonable personal criticism. It's just the money and part of doing business. You have a lawful obligation to file your tax return, and if you don't file or pay, they have extrodinary rights that will make your life miserable. Far worse than bankrupcy (bankrupcy does not forgive back taxes.) But since penalties and interest are based on money owed, and you made a payment, then this concern may be irrelevant. Since they've sent you warning letters, then you are in the hot box. My recommedation is to take your return to a tax pro to look over. I really doubt that will cost much at all as many pros don't even charge for the 1st meeting as they are looking you over as much as you are sizing them up. They will point out any obvious flaws and you can ask for a quote to clean it up before you make a commitment to them. A preparers signature at the bottom does carry weight and will reduce the likelyhood of excessive penalties. I've always had trouble with tax software as it will spit out different numbers each time I have ran it. I like to go onto the IRS web site http://www.irs.ustreas.gov/formspubs/index.html and use the fill in forms. This gives you a very clean looking return that the pro can look at more efficiently and looks good to Uncle Sammy as well. Best Wishes.
Yes, I do take advantage of all I can. That's why I had a respected CPA prepare it for me 15 years ago. Each subsequent year it's basically the same with different numbers. Actually it's rather easy to do ... I can almost do it in my sleep. And I have 10-15 forms and schedules to attach yearly. You seem to imply that it takes hours of time to prepare a tax return ... and that's a waste of time ... yet you also seem to complain about the cost of going to a CPA or tax preparer ... can't have it both ways. Either learn the tax code as it applies to you or pay someone to do it. In either case it takes someone TIME to do the forms ... and time is worth money, whether it's your own or someone else's.
I know I'm coming to this party a little late but I recall (and perhaps maggandre will correct me if I am wrong) that the monetary penalty for filing your tax return late is more severe that submitting payment late or not submitting payment with your return. If this is the case (assuming you can complete your return) you would want to submit your return even if you are uncertain about how much you owe.