You could use the Directory on LDS.org. for each ward, go to the ward organizations and then go to the Elders and High Priests and priests and teachers and deacons and choose the e-mail link. For a stake of ten wards, that's 50 steps. Not too fun.
If you have access to MLS, you could create a custom report to include each MP and AP holder and extract their Contact Email address. Then copy the results into your e-mail program and send. But be careful -- many e-mail service providers have limits on bulk emails.
Questions that can benefit the larger community should be asked in a public forum, not a private message.