Check out the Echo lineup . They have some light weight units that are very easy to handle and start .

Echo and Stihl both make easy start models. Others probably do also, but I'm not familiar with them. Stihl and Echo units are going to weigh around 10.5 lbs with trimmer head attached and a full tank of gas. I would suggest, if at all possible, that you go try a few at dealers near you. I've got a Stihl blower with their easy start system (less effort required to pull the cord) and am not real fond of it. The blower is great, but there isn't the same feel to the easy start system that I'm used to in the regular models. That may not be a concern for you since you find a regular model too hard to crank, but its a slight annoyance to me. If I used it more often I'm sure I would get used to it. Also, being a woman, you're probably around 5 to 5.5 feet, look at curved shaft trimmers, they are usually more suited to people of shorter stature. I was recently at Home Depot and happpened to notice the price on an Echo blower they had for sale. It was $10 more than MSRP on Echo's website, so it might pay you to shop around at other dealers, especially ones that can service the products they sell.

I've had a battery operated trimmer in the past and really liked it. Mine was a Ryobi made Toro, but I know B&D makes them too. Pros: 1) No emissions 2) Always start/ run 3) Quiet. 4) battery life typically fine for an average yard and then some. Several have a hanger/ charger that you fasten to the garage wall. When you're done, hang the trimmer up and it recharges and maintains the battery on it's own. If you have a choice, buy one with a larger swath. It's not like you will cutting paths through a field with it, but the line will last longer and it will be more effective. Know that the projected battery life will be on the long side. So if it says lasts an hour, figure on the second year you will probably be at 30 minutes or so. But again, typically fine for most people. Maybe someone with a current model will chime in.