You can stop frequent calls by salespeople by contacting your network provider to block the numbers. However, you should ensure that you unsubscribe to some sites you signed up for on the internet so as to reduce the number of people calling you for sales.
Act like your a police detective investigating a murder at the house when you answer them. Then start questioning them on how they know you, and why they have made calls to your number. Insist that you need there contact information for questioning the murder and tell them they need to go to police Headquarters for questioning.
Ok. I worked for a bk lawyer and the clients forwarded all their collection calls to lucky ol Me!! So all day long-8 hrs-my job was to a answer ALL the collection calls!! Fun, right? The only real way to stop the calls is to file bankruptcy, by law they can't contact you if you're legally represented. I had one client tell the creditors her "husband" died and that his attorney will handle his debt. This woman sent her dead brothers death cert to the creditors, and after a while they found out she lied and is now serving her last 2 months of her 24 month sentence for credit fraud, paying over $300,000 in fines, and is still in credit debt. If it's just sales calls, tell em "hey, I'm really interested, but here's the right number to call me: ". Give them a random number out of the phone book and call it a day.
This is how I deal with it -- I was always getting calls from this fake, Canadian debt-collection company (meaning I couldn't report them, because they're outside the country, and they didn't have a no-call list). So one day, I answered the phone and said in this curt, professional way, "Hello? Who is this?" This conversation ensued:
Canadian debt-collector: "Hello? This is the Tackar Group calling. Is this Harper MacDonald?"
Me: "No. Ms. MacDonald has been arrested for cocaine smuggling. This house is currently under lock-down, and is occupied by the FBI."
Canadian debt-collector: "Wait, what? Is -- "
Me: "All calls to this residence are being traced, and may be called in for questioning. You may be held liable under foreign law for associating with a known criminal. Do you understand?"
Canadian debt-collector: "Wait, wait, I don't understand. . . "
I started to read off the Miranda rights (it sounded good), and the caller hung up on me. I never got a call from them since. ;)