Though that sounds like a good plan. I agree with the people here. You should first build a base list using JV giveaways or a free WSO in Warriorforum.com.
Once you have around 250 people in your list, you can find some adswap partners.
Just a word of warning. Though solo ads may seem like a good source of optin traffic, it is not. So be sure to ask the list owner about the list and its conversion rate before agreeing.