I spent many years working with business closures and WARN notices and the lack of notice. The thing is, they can legally sell, close down and with this number of employees, you work all day one fine day and then they call you in and notify you of it, and that is the first you have heard of it. It happens all the time.
But you have gotten a "rumor notice" which is after all, better than no notice at all. No job in the world is guaranteed secure. Which means that instead of yelling and carrying on about how this has worked out, begin right now to make pro active moves about getting copies of your good evals, collecting information about the workplace, dates you have worked there, addresses of your references, etc. for future job hunts. Then brace up your resume and very quietly, while still working, begin looking for other jobs.
Until you HAVE that other job, with an offer and a start date set in stone, keep working at this one. Ride the horse into the ground or until you have another horse to change to. DO NOT QUIT THE JOB BECAUSE THEY ARE CLOSING. this is the biggest mistake I saw people make often. You will not if you do this, qualify for unemployment benefits. And surprisingly, people did it frequently, thinking it was really going to pay that mean old company back, or salvage their pride or make them look better or something!?!
Wait until they tell you they have sold and are closing. Wait until you have worked your official last day for them. Then you file for unemployment benefits. Do this even if you are told you are going to receive severance or vacation pay. Do this even if you have not yet received your last pay check. Let the unemployment system tell you how they'll count this.
Do this even if they say the new owner would be willing to offer you a job at the new business on the other side of town. (Unless you really really would prefer to go to the new worksite and work. If so, go for it.) Do this (file) even if you are 'pretty sure' you can get a job in a few weeks down there where your cousin Eddie works, because you heard they were hiring.
Do this even if your wife or husband is a lottery winner or a Wall Street banker, and you don't "need" the money from unemployment benefits. It's not based on needs, it is an insurance program that is paid for by the employer to cover you with a small amount of income if you are put out of a job through no fault of your own, which is what is happening here. So in a way you can say that if an employer, regardless of size, puts you out of work by selling their business, unemployment is the penalty they have pre paid, and that's what unemployment is for.
The new employer/owner of the company may say you MUST come to work for them at their new plant, (because if you do not, it will increase their unemployment taxes when they shut this one down and you workers apply for benefits). They might be tempted to lie to you for their profit, imagine that!
But it is not the same employer, you have been put out of work for xxx company, and people cannot be bought and sold like companies can. You are not forced to come to work at the new company. You have the right to apply for unemployment benefits and let them determine if a job a significant distance further than you were driving is an equivalent job. You can perhaps find another job that is more equivalent in distance. Just file that claim after your last day of work and let the system work as it should.
Make sure you catch your finances up as much as possible right now, because in any case where you are going to be put out of work, there is going to be a gap in your income. Best case, it takes a few weeks for unemployment benefits to begin. Even if you qualify and it is a smooth process to be approved for benefits, there will be a three to five week gap from the time you file the claim until you begin receiving regular weekly checks. The unemployment that you will likely be able to draw if the business is selling will probably be less than you would've made working, too, and it will only last 26 weeks, no matter how bad you need it or what the situation is with you personally.
Good luck to you. Many people find that when something like this happens, a company closes like this, and things change, the new situation you find yourself in turns out to be better than the old one was. We all tend not to make changes, even good ones, until we are forced to do so. Hopefully, you will find a better job soon to replace this one.