Unless you are a cash buyer and can provide proof of funds to show your ability to purchase a home, a preapproval is not only paramount but an important requisite in determining not only what you can afford but also what you will be comfortable with in terms of monthly mortgage payment and all other costs that will be part of the mortgage payment such as property taxes, PMI(depending on the type of financing) and home owner's insurance.
What would you feel if you find the right home only to discover that you are not in that position yet to acquire that property? Wouldn't that disappoint and dishearten you?
Save yourself, the showing agent, the listing agent and the seller the trouble by following the guidelines in home ownership process.
Prequalification is not a daunting task. All it takes is a consultation with a local and competent loan officer/mortgage broker.
Some mortgage professionals on this forum will be gladly lend you the assistance you need to get you started.