what are legal options I have?

As you say that she quarrels for trivial issues you can adjust with her to lead the life.  Having lived for 8 years together it is not wise to break the relationship now.  I suggest you speak to her gently and get to know her wishes/demands.  Try to fulfil her wishes and if possible change yourself for her.  Because taking legal recourse may create more loss of mental peace and monetary loss. 

But if you think the problems are out of control and living with her is almost impossible then you may speak to her gently and discuss the easy way to end the relationship by way of mutual consent divorce (section 13B).  It is last and best option.  If you are able to convince her for mutual consent divorce certainly you may get divorce without any hassles in about 6 - 7months time frame. 

Good Luck.

1. Lodge a police complaint immediately to locate her.

2. Send a lawyer notice to her to immediately return and resume conjugal rights.

As a responsible husband, it is necessary on your part to later prove that you have taken reasonably prudent legal steps and the wife has left on her own volition and not due to any fault from your side. Second, you have a right to demand restitution of conjugal rights from wife. In case, she wants to get divorce, she will send a reply as such and you can proceed accordingly. In case she does not respond to the notice, you can file a case for restitution of conjugal rights. If there is any disobedience to the court orders, that will be a strong ground for you to claim there is irretrievable broken marriage and there is no meaning in continuing such a matrimony and seek divorce.