It really isn't that hard at all. If you buy the tulle in rolls (from the wedding aisle) you could probably make one tutu in 30 minutes.
Yup, this.
And to get the strips to all be the same length wrap the tulle around a piece of cardboard cut to length, hold it down with rubber bands and then just cut both sides. Makes things go waaaaaay faster.
It totally depends on your level of OCD. Audrey's "rainbow ballerina" tutu for Halloween took me forever but she was "helping" and I was getting crazy.
I made one for E's Halloween costume and it was super easy but time consuming. However, I wish I had known the measuring/cutting tip. That was the most time-consuming part. And I also had a couple of different colors. I might also advise against using 'sparkly' tulle - it is super cute but it also makes a huge mess. I used thin elastic for the waistband and it stretched out as I tied the knots, so I had to cut it smaller to fit snugly around E's waist after I was finished.
I bought all my tulle at HL - it comes in rolls and they were half off. So you may want to keep an eye out for the next sale?
Re: Make your own tutu?
Yup, this.
And to get the strips to all be the same length wrap the tulle around a piece of cardboard cut to length, hold it down with rubber bands and then just cut both sides. Makes things go waaaaaay faster.
there were tons of pins on tutu making on pinterest
looked pretty quick 
It totally depends on your level of OCD. Audrey's "rainbow ballerina" tutu for Halloween took me forever but she was "helping" and I was getting crazy.
I made one for E's Halloween costume and it was super easy but time consuming. However, I wish I had known the measuring/cutting tip. That was the most time-consuming part. And I also had a couple of different colors. I might also advise against using 'sparkly' tulle - it is super cute but it also makes a huge mess. I used thin elastic for the waistband and it stretched out as I tied the knots, so I had to cut it smaller to fit snugly around E's waist after I was finished.
I bought all my tulle at HL - it comes in rolls and they were half off. So you may want to keep an eye out for the next sale?