This is great to hear that you have made improvements to your diet as well have stopped smoking!
While it is true that you can obtain these prescriptions online, and it is also true that this is not legal, an even more important consideration is that a doctor's appointment can help determine the root cause of your potential ED, and whether a medication would be helpful for you or not.
For example, if you are suffering from low testosterone, a drug like viagra, cialis, or levitra would not be helpful because while these medications help you keep an erection, testosterone is partially responsible for obtaining one. Also, heart or blood pressure issues could contribute to ED symptoms, and lastly the culprit could be psychological, in which case the best treatment would be medication for anxiety/depression, or possibly counseling. So in the end, sometimes ED cannot be treated with medication if the root cause doesn't match how the medication works.
All of these examples require a different treatment strategy, as well as a different work-up. In addition, there are several medical conditions (high blood pressure for example), and several medications that you cannot take in combination with viagra, levitra, or cialis (those same medications that treat blood pressure!).
This all being said, money is an important consideration when thinking about going the route of making a doctor's appointment and obtaining a prescription. If you are interested, you can PM me and I will direct you to coupons that you can take to your doctor and pharmacy that can get you a free sample of these medications. I can also detail you the common retail price if you are interested.
Hope this helps!