The company I used to work for was on a bi-monthly payroll, which was the 1st -15th, and 16th - end of the month.

My question is, I was paid for a consistent 106-108 hours every pay period (4hrs SU, 8hrs M-TH, 2 1/2 F, 7hrs Sat, *A couple times an extra 30min-1 1/2hr were put in a week)

Many times I did not receive any over time, if I did receive overtime it was typically 3-6 hours, shouldn't I be owed more overtime?

I was told by the company that there format worked like this;

Example is January 2007;
1st (Mon) - 6th (Sat) 1 week
7th (Sun) - 13th (Sat) 1 week
14th (Sun) - 15th (Mon) - applied to next pay period

16th (Tue) - 20th (Sat) 1 week
21st (Sun) - 27th (Sat) 1 week
28th (Sun) - 31st - applied to next pay period (Feb 1st-15th)

I've spoken to companies who use the same pay period, and there pay period is much easier to follow, and days do not carry over to the next pay period/month. Is this company wrong, and could I possibly be owed money?

A payweek needs to be specifically defined. Either Sun-Sat, Mon-Sun, etc. Once that is defined, your OT calc will be based on the hours for that week.

The payroll period and the payweek can be different things.

I'm told it was Sun-Sat, this is why for the example above, you'll nottice that they run Sun-Sat when possible. The above format was how I was told it works, as every time I did question them about the issue, I was given different answers. I have had issues with them concerning the amount of pay/hours being correct, and on more then one occasion my pay check was off by $40+ and I had to bring it to there attention so they would correct it, this is why I question the overtime.

Overtime laws vary by nation ( canada, US, Iran? )

And if in the US by state. There are many business and industry that are exempt from overtime and don't pay it.

And depending on the state, overtime may be looked at by the day, or by the week, or by the pay period.

You need to sit down with HR and have them explain it, and if you believe it is wrong you can contact the department of labor for a review of it.